Graphene‐based textiles show promise for next‐generation wearable electronic applications due to their advantages over metal‐based technologies. However, current reduced graphene oxide (rGO)‐based ...electronic textiles (e‐textiles) suffer from poor electrical conductivity and higher power consumption. Here, highly conductive, ultraflexible, and machine washable graphene‐based wearable e‐textiles are reported. A simple and scalable pad−dry−cure method with subsequent roller compression and a fine encapsulation of graphene flakes is used. The graphene‐based wearable e‐textiles thus produced provide lowest sheet resistance (≈11.9 Ω sq−1) ever reported on graphene e‐textiles, and highly conductive even after 10 home laundry washing cycles. Moreover, it exhibits extremely high flexibility, bendability, and compressibility as it shows repeatable response in both forward and backward directions before and after home laundry washing cycles. The scalability and multifunctional applications of such highly conductive graphene‐based wearable e‐textiles are demonstrated as ultraflexible supercapacitor and skin‐mounted strain sensors.
Highly conductive and machine washable graphene‐based wearable e‐textiles are produced using a highly scalable pad−dry−cure method with subsequent roller compression and a fine encapsulation of graphene flakes. Mutifunctional graphene textiles thus produced would be an important step toward moving from R&D‐based e‐textiles to actual real world applications.
Rechargeable alkali metal‐ion batteries (AMIBs) are receiving significant attention owing to their high energy density and low weight. The performance of AMIBs is highly dependent on the electrode ...materials. It is, therefore, quite crucial to explore suitable electrode materials that can fulfil the future requirements of AMIBs. Herein, a hierarchical hybrid yolk–shell structure of carbon‐coated iron selenide microcapsules (FeSe2@C‐3 MCs) is prepared via facile hydrothermal reaction, carbon‐coating, HCl solution etching, and then selenization treatment. When used as the conversion‐typed anode materials (CTAMs) for AMIBs, the yolk–shell FeSe2@C‐3 MCs show advantages. First, the interconnected external carbon shell improves the mechanical strength of electrodes and accelerates ionic migration and electron transmission. Second, the internal electroactive FeSe2 nanoparticles effectively decrease the extent of volume expansion and avoid pulverization when compared with micro‐sized solid FeSe2. Third, the yolk–shell structure provides sufficient inner void to ensure electrolyte infiltration and mobilize the surface and near‐surface reactions of electroactive FeSe2 with alkali metal ions. Consequently, the designed yolk–shell FeSe2@C‐3 MCs demonstrate enhanced electrochemical performance in lithium‐ion batteries, sodium‐ion batteries, and potassium‐ion batteries with high specific capacities, long cyclic stability, and outstanding rate capability, presenting potential application as universal anodes for AMIBs.
Herein, a yolk–shell structure of iron selenide nanoparticles within carbon shell microcapsules is introduced as a universal electrode for alkali ion batteries. The internal voids can alleviate volume expansion while the interconnected external carbon shell promotes mechanical strength. Hence, the microcapsules exhibit enhanced electrochemical performance with high specific capacities, long cyclic stability, and outstanding rate capability.
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Utilising the solid-state synthesis method is an easy and effective way to recycle spent lithium-ion batteries. However, verifying its direct repair effects on completely exhausting ...cathode materials is necessary. In this work, the optimal conditions for direct repair of completely failed cathode materials by solid-state synthesis are explored. The discharge capacity of spent LiCoO2 cathode material is recovered from 21.7 mAh g−1 to 138.9 mAh g−1 under the optimal regeneration conditions of 850 °C and n(Li)/n(Co) ratio of 1:1. The regenerated materials show excellent electrochemical performance, even greater than the commercial LiCoO2. In addition, based on the whole closed-loop recycling process, the economic and environmental effects of various recycling techniques and raw materials used in the battery production process are assessed, confirming the superior economic and environmental feasibility of direct regeneration method.
A novel top-down electrochemical method is demonstrated to prepare gram quantities of few-layer graphene in a single-step, one-pot process. Potential-controlled cathodic reduction is used to ...intercalate graphite electrodes with alkali-substituted, ammonium- and dimethyl sulfoxide-solvated cations. In situ decomposition of the intercalated compounds breaks the π–π stacking of the graphene layers along the c axis of the graphite gallery, producing 1–20-μm-diameter few-layer graphene sheets, without the need for defect-inducing oxidative or sonication treatments. With a slight modification of the electrodes’ configuration, the process can run in a continuous manner, presenting a potentially scalable approach for few-layer graphene production.
Herein we present a green and facile approach to the successful reduction of graphene oxide (GO) materials using molten halide flux at 370 °C. GO materials have been synthesized using a modified ...Hummers method and subsequently reduced for periods of up to 8 h. Reduced GO (rGO) flakes have been characterized using X-ray-diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FTIR), all indicating a significantly reduced amount of oxygen-containing functionalities on the rGO materials. Furthermore, impressive electrical conductivities and electrochemical capacitances have been measured for the rGO flakes, which, along with the morphology determined from scanning electron microscopy, highlight the role of surface corrugation in these rGO materials.
Smart and multifunctional fiber reinforced polymer (FRP) composites with energy storage, sensing, and heating capabilities have gained significant interest for automotive, civil, and aerospace ...applications. However, achieving smart and multifunctional capabilities in an FRP composite while maintaining desired mechanical properties remains challenging. Here, a novel approach for layer‐by‐layer (LBL) deposition of 2D material (graphene and molybdenum disulfide, MoS2)‐based heterostructure onto glass fiber fabric using a highly scalable manufacturing technique at a remarkable speed of ≈150 m min−1 is reported. This process enables the creation of smart textiles with integrated energy storage, sensing, and heating functionalities. This methodology combines gel‐based electrolyte with a vacuum resin infusion technique, resulting in an efficient and stable smart FRP composite with an areal capacitance of up to ≈182 µF cm−2 at 10 mV s−1. The composite exhibits exceptional cyclic stability, maintaining ≈90% capacitance after 1000 cycles. Moreover, the smart composite demonstrates joule heating, reaching from ≈24 to ≈27 °C within 120 s at 25 V. Additionally, the smart composite displays strain sensitivity by altering electrical resistance with longitudinal strain, enabling structural health monitoring. These findings highlight the potential of smart composites for multifunctional applications and provide an important step toward realizing their actual real‐world applications.
The layer‐by‐layer deposition of 2D material (graphene and MoS2)‐based heterostructure onto glass fiber fabric using a highly scalable manufacturing technique is reported. This process enables the creation of smart and multifunctional fiber reinforced composites with integrated energy storage, sensing, and heating functionalities.
•• We developed a triple-shell microsphere composed of NiO nanoparticles for p-DSSCs.•• The inner cavities and the excellent light reflection of the triple-shell enhanced their scattering ability.•• ...The new photocathode showed excellent photoelectrochemical performance, with a photoelectrical efficiency of 1.79%
In this article, new p-DSSC electrodes are fabricated using NiO hollow spheres (HSs) prepared through a facial one-step hydrothermal process. The current-voltage (J-V) curve indicates that p-DSSCs fabricated using triple-shell NiO HS have excellent photoelectrochemical performance, with a photoelectrical efficiency of 1.79%. The UV–vis diffused reflectance spectra indicate that the triple-shell NiO HS, with its unique structure, has superior light reflection, scattering ability and large surface area with more inner cavities, which helps harvest more light. Electrochemical impedance spectroscopy (EIS) further confirms that triple-shell NiO HS shows fast dye regeneration, improved hole transport and suppressed recombination. The research work of unique NiO HS is important for the selection of efficient photocathode materials for p-DSSCs.
The rational design of cost-effective and efficient electrocatalysts for electrochemical water splitting is essential for green hydrogen production. Utilizing nanocatalysts with abundant active ...sites, high surface area, and deliberate stacking faults is a promising approach for enhancing catalytic efficiency. In this study, we report a simple strategy to synthesize a highly efficient electrocatalyst for the hydrogen evolution reaction (HER) using carbonized luffa cylindrica as a conductive N-doped carbon skeleton decorated with Ag nanorings that are activated by introducing stacking faults. The introduction of stacking faults and the resulting tensile strain into the Ag nanorings results in a significant decrease in the HER overpotential, enabling the use of Ag as an efficient HER electrocatalyst. Our findings demonstrate that manipulating the crystal properties of electrocatalysts, even for materials with intrinsically poor catalytic activity such as Ag, can result in highly efficient catalysts. Further, applying a conductive carbon backbone can lower the quantities of metal needed without compromising the HER activity. This approach opens up new avenues for designing high-performance electrocatalysts with very low metallic content, which could significantly impact the development of sustainable and cost-effective electrochemical water-splitting systems.
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